Fuel cell system

Patent metadata

Field	Value
Publication number	US-10741858-B2
Application number	US-201515521819-A
Country	US
Kind code	B2
Filing date	Nov 25, 2015
Priority date	Nov 27, 2014
Publication date	Aug 11, 2020
Grant date	Aug 11, 2020

Abstract

A fuel cell system includes: a fuel cell; a reformer to generate a hydrogen-containing gas; an electric power generation raw material supply unit; a reforming material supply unit configured to supply at least one of reforming water and reforming air, to the reformer; an oxidizing gas supply unit to supply an oxidizing gas to a cathode of the fuel cell; a combustor to ignite an exhaust gas discharged from the fuel cell; and a controller. In an operation stop process of the fuel cell system, the controller causes the oxidizing gas supply unit to supply the oxidizing gas, causes the electric power generation raw material supply unit and the reforming material supply unit to intermittently supply the electric power generation raw material and at least one of the water and the air to the reformer, and causes the ignitor to perform an ignition operation.

First claim

The invention claimed is:

1. A fuel cell system comprising:
a solid-oxide fuel cell;
a reformer operative to reform an electric power generation raw material to generate a hydrogen-containing gas and supply the hydrogen-containing gas to an anode of the solid-oxide fuel cell;
an electric power generation raw material supply unit operative to supply the electric power generation raw material to the reformer;
a reforming material supply unit operative to supply at least one of reforming water and reforming air, utilized in a reforming reaction, to the reformer;
an oxidizing gas supply unit operative to supply an oxidizing gas to a cathode of the solid-oxide fuel cell;
a combustor including an ignitor operative to ignite an exhaust gas discharged from the solid-oxide fuel cell; and
a controller including a processor and a non-transitory memory storing a control program, wherein
the control program, when executed by the processor causes the controller, in an operation stop process of the fuel cell system, to cause the oxidizing gas supply unit to supply the oxidizing gas to the cathode of the solid-oxide fuel cell, to cause the electric power generation raw material supply unit and the reforming material supply unit to intermittently supply the electric power generation raw material and the at least one of the water and the air to the reformer, and to cause the ignitor of the combustor to perform an ignition operation.

2. The fuel cell system according to claim 1 , further comprising:
a purifier provided downstream of the combustor to purify a combustible gas contained in a flue gas discharged from the combustor; and
a purifier temperature detecting portion operative to detect a temperature of the purifier as a temperature detecting portion operative to detect a temperature of the fuel cell system, wherein
when a detection result of the purifier temperature detecting portion is less than a predetermined temperature, the program further causes the controller to cause the ignitor to perform the ignition operation.

3. The fuel cell system according to claim 1 , further comprising a desulfurizer operative to remove a sulfur compound contained in the electric power generation raw material.

4. The fuel cell system according to claim 3 , further comprising a heater portion through which the exhaust gas combusted in the combustor flows and which is operative to heat the desulfurizer by heat of the combusted exhaust gas.

5. The fuel cell system according to claim 3 , wherein the desulfurizer is a hydro-desulfurizer operative to utilize hydrogen to remove the sulfur compound from the electric power generation raw material.

6. The fuel cell system according to claim 1 , wherein the program further causes the controller to cause the electric power generation raw material supply unit and the reforming material supply unit to intermittently supply the electric power generation raw material and the at least one of the water and the air to the reformer at predetermined time intervals.

7. The fuel cell system according to claim 3 , wherein temperatures of the reformer, the solid-oxide fuel cell, and the desulfurizer change in conjunction with one another,
the fuel cell system further comprising, as a temperature detecting portion operative to detect a temperature of the fuel cell system, at least one of a reformer temperature detecting portion operative to detect the temperature of the reformer, a fuel cell temperature detecting portion operative to detect the temperature of the solid-oxide fuel cell, and a desulfurizer temperature detecting portion operative to detect the temperature of the desulfurizer, wherein
based on whether or not the temperature detected by the at least one of the reformer temperature detecting portion, the fuel cell temperature detecting portion, and the desulfurizer temperature detecting portion falls within a predetermined temperature range, the program further causes the controller to cause the electric power generation raw material supply unit and the reforming material supply unit to intermittently supply the electric power generation raw material and the at least one of the water and the air to the reformer.

8. The fuel cell system according to claim 7 , wherein based on an increased value or decreased value of the temperature detected by the at least one of the reformer temperature detecting portion, the fuel cell temperature detecting portion, and the desulfurizer temperature detecting portion, the program further causes the controller to cause the electric power generation raw material supply unit and the reforming material supply unit to intermittently supply the electric power generation raw material and the at least one of the water and the air to the reformer.

9. The fuel cell system according to claim 1 , further comprising:
a combustible gas channel which is a channel extending from the electric power generation raw material supply unit to the anode of the solid-oxide fuel cell and through which a combustible gas containing the electric power generation raw material flows; and
a pressure sensor provided at the combustible gas channel to detect pressure in the combustible gas channel, wherein
when the pressure in the combustible gas channel is negative pressure as a detection result of the pressure sensor, the program further causes the controller to cause the electric power generation raw material supply unit and the reforming material supply unit to intermittently supply the electric power generation raw material and the at least one of the water and the air to the reformer at predetermined time intervals.

10. The fuel cell system according to claim 1 , further comprising a voltage detector operative to detect a voltage of the solid-oxide fuel cell, wherein
each time the voltage detected by the voltage detector becomes a predetermined voltage or less, the program further causes the controller to cause the electric power generation raw material supply unit and the reforming material supply unit to supply the electric power generation raw material and the at least one of the water and the air to the reformer.

11. The fuel cell system according to claim 9 , wherein the reforming material supply unit is a reforming water supply unit operative to supply the reforming water, utilized in the reforming reaction, to the reformer,
the fuel cell system further comprising:
an evaporator operative to evaporate the water supplied from the reforming water supply unit to the reformer;
a heater operative to heat the evaporator; and
an oxidizing gas channel through which the oxidizing gas flows and which is a channel extending from the oxidizing gas supply unit to the solid-oxide fuel cell, wherein
temperatures of the evaporator, the reformer, and the solid-oxide fuel cell change in conjunction with one another,
the fuel cell system further comprising, as a temperature detecting portion operative to detect a temperature of the fuel cell system, at least one of an evaporator temperature detecting portion operative to detect the temperature of the evaporator, a reformer temperature detecting portion operative to detect the temperature of the reformer, and a fuel cell temperature detecting portion operative to detect the temperature of the solid-oxide fuel cell, wherein
in the operation stop process of the fuel cell system, the program further causes the controller to cause the electric power generation raw material supply unit and the reforming water supply unit to supply the electric power generation raw material and the water to the combustible gas channel and to cause the oxidizing gas supply unit to supply the oxidizing gas to the oxidizing gas channel, and when the control

Assignees

• Panasonic Corp
• Morimura Sofc Tech Co Ltd

Inventors

• Onuma Shigenori
• Ukai Kunihiro
• Shirahama Hiroshi
• Saito Takeshi
• Akagi Yosuke
• Sakamoto Taiichiro
• Ooe Toshiharu
• Otsuka Toshiharu

Classifications

• Y02E60/50

  Fuel cells · CPC title

• H01M8/04388

  of anode reactants at the inlet or inside the fuel cell · CPC title

• H01M8/04201

  Reactant storage and supply, e.g. means for feeding, pipes · CPC title

• H01M8/04089

  of gaseous reactants · CPC title

• H01M8/04753

  of fuel cell reactants · CPC title